Non-combustible Tobacco Products Research Articles

High-throughput cell-based assays for identifying antagonists of multiple smoking-associated human nicotinic acetylcholine receptor subtypes

There is substantial evidence that in addition to nicotine, other compounds found in tobacco smoke significantly influence smoking behavior. Further, recent years have seen an explosion in the availability of non-combusted products that deliver nicotine, such as e-cigarettes and “home-brew” vaping devices that are essentially unregulated. There are many thousands of compounds in tobacco smoke alone, and new products are constantly introducing new compounds. Uncovering which of these compounds are active, across multiple smoking-relevant subtypes of the nicotinic acetylcholine receptor (nAChR) that influence tobacco/nicotine addiction, requires a high-throughput screening (HTS) approach. Accordingly, we developed a panel of HTS-friendly cell-based assays, all performed in the same cellular background and using the same membrane potential dye readout, to measure the function of the α3β4-, α4β2-, and α6β2-nAChR subtypes. These subtypes have each been prominently and consistently associated with human smoking behavior. We validated our assays by performing pilot screening of an expanded set of the Prestwick FDA-approved drug library. The screens displayed excellent performance parameters, and moderate hit rates (mean of 1.2% across all three assays) were achieved when identifying antagonists (chosen since effects of endogenous antagonists on consumption of nicotine/tobacco products are under-studied). Validation rates using an orthogonal assay (86Rb+ efflux) averaged 73% across the three assays. The resulting panel of assays represents a valuable new platform with which to screen and identify nAChR subtype-selective compounds. This provides a resource for identifying smoking-related compounds in both combusted and non-combusted tobacco products, with potential relevance in the search for additional smoking-cessation therapies.

Combined Associations of Changes in Noncombustible Nicotine or Tobacco Product and Combustible Cigarette Use Habits With Subsequent Short-Term Cardiovascular Disease Risk Among South Korean Men: A Nationwide Cohort Study.

The associations of changes in noncombustible nicotine or tobacco product (NNTP) and combustible cigarette (CC) use habits with subsequent cardiovascular disease (CVD) risk are still unclear. The study population consisted of 5 159 538 adult men who underwent health screening examinations during both the first (2014-2015) and second (2018) health screening periods from the Korean National Health Insurance Service database. All participants were divided into continual CC-only smokers, CC and NNTP users, recent (<5 years) CC quitters without NNTP use, recent CC quitters with NNTP use, long-term (≥5 years) CC quitters without NNTP use, long-term CC quitters with NNTP use, and never smokers. Propensity score matching analysis was conducted to further compare CVD risk among CC quitters according to NNTP use. Starting from the second health screening date, participants were followed up until the date of CVD event, death, or December 31, 2019, whichever came earliest. Multivariable Cox proportional hazards regression was used to determine the adjusted hazard ratios (aHRs) and 95% CIs for CVD risk according to changes in NNTP and CC smoking habits. Compared with continual CC-only smokers, CC and NNTP users (aHR, 0.83 [95% CI, 0.79-0.88]) and initial CC smokers who quit CCs and switched to NNTP use only (recent CC quitters with NNTP use, aHR, 0.81 [95% CI, 0.78-0.84]) had lower risk for CVD. After propensity score matching, recent CC quitters with NNTP use (aHR, 1.31 [95% CI, 1.01-1.70]) had higher risk for CVD than recent CC quitters without NNTP use. Similarly, compared with long-term CC quitters without NNTP use, long-term CC quitters with NNTP use (aHR, 1.70 [95% CI, 1.07-2.72]) had higher CVD risk. Switching to NNTP use among initial CC smokers was associated with lower CVD risk than continued CC smoking. On CC cessation, NNTP use was associated with higher CVD risk than CC quitting without NNTPs. Compared with CC smokers who quit without NNTP use, CC quitters who use NNTPs may be at higher future CVD risk.

Validation of the Wave 1 and Wave 2 Population Assessment of Tobacco and Health (PATH) Study Indicators of Tobacco Dependence Using Biomarkers of Nicotine Exposure Across Tobacco Products.

This study examined the predictive relationships between biomarkers of nicotine exposure and 16-item self-reported level of tobacco dependence (TD) and subsequent tobacco use outcomes. The Population Assessment of Tobacco and Health (PATH) Study surveyed adult current established tobacco users who provided urine biospecimens at Wave 1 (September 2013-December 2014) and completed the Wave 2 (October 2014-October 2015) interview (n = 6872). Mutually exclusive user groups at Wave 1 included: Cigarette Only, E-cigarette Only, Cigar Only, Hookah Only, Smokeless Tobacco Only, Cigarette Plus E-cigarette, multiple tobacco product users who smoked cigarettes, and multiple tobacco product users who did not smoke cigarettes. Total Nicotine Equivalents (TNE-2) and TD were measured at Wave 1. Approximate one-year outcomes included frequency/quantity used, quitting, and adding/switching to different tobacco products. For Cigarette Only smokers and multiple tobacco product users who smoked cigarettes, higher TD and TNE-2 were associated with: a tendency to smoke more, smoking more frequently over time, decreased likelihood of switching away from cigarettes, and decreased probability of quitting after one year. For other product user groups, Wave 1 TD and/or TNE-2 were less consistently related to changes in quantity and frequency of product use, or for adding or switching products, but higher TNE-2 was more consistently predictive of decreased probability of quitting. Self-reported TD and nicotine exposure assess common and independent aspects of dependence in relation to tobacco use behaviors for cigarette smokers. For other product user groups, nicotine exposure is a more consistent predictor of quitting than self-reported TD. This study suggests that smoking cigarettes leads to the most coherent pattern of associations consistent with a syndrome of TD. Because cigarettes continue to be prevalent and harmful, efforts to decrease their use may be accelerated via conventional means (eg, smoking cessation interventions and treatments), but also perhaps by decreasing their dependence potential. The implications for noncombustible tobacco products are less clear as the stability of tobacco use patterns that include products such as e-cigarettes continue to evolve. TD, nicotine exposure measures, and consumption could be used in studies that attempt to understand and predict product-specific tobacco use behavioral outcomes.

Knowledge and Perceptions of Tobacco-Related Harm Associated with Intention to Quit among Cigarette Smokers, e-Cigarette Users, and Dual Users: Findings from the US Population Assessment of Tobacco and Health (PATH) Wave 1

Objective: To study the association between knowledge of diseases caused by smoking, perceptions of harm of cigarettes and intention to quit among cigarettes and e-cigarettes users. Methods: Using US Population Assessment of Tobacco and Health (PATH) Wave 1 data (2013–2014), we investigated the mean knowledge of diseases due to smoking and perceptions of harm of cigarettes scores among cigarette smokers (n = 8,263), e-cigarette users (n = 829), and dual users (n = 745) and examined the association between knowledge, perceptions of harm and intention to quit. Results: E-cigarette users had the highest scores in both knowledge and perceptions of harm items. We found a stronger association between knowledge and intention to quit among females (aOR: 1.25; 95% CI: 1.18, 1.34) compared to males (aOR: 1.11; 95% CI: 1.05, 1.18). We observed a strong association between perceptions of harm and intention to quit among cigarette smokers (p < 0.0001) and dual users (p = 0.0001), but not e-cigarette users. Conclusions: Our study indicates it is urgent for federal and state governments to develop comprehensive guidelines for targeted health messaging regarding the harms of cigarettes, noncombustible tobacco products, and dual use, and the benefits of cessation. Further, findings suggest that effective health education should include tobacco product-specific risks and the comprehensive negative health impacts of tobacco given the strong positive association of perceptions of harm and intention to quit. Supplemental data for this article is available online at https://doi.org/10.1080/10826084.2021.1879145.

Alternative tobacco products use and its impact on urologic health - will the lesser evil still be evil? A commentary and review of literature.

IntroductionAlternative tobacco products, including electronic cigarettes (e-cigarettes) and non-combustible tobacco products or heat-not-burn (HNB) products, are substitutes to conventional combustible cigarettes with the potential to impact urologic health, similar to traditional smoking. Most urologists, however, have limited knowledge of these products and are unfamiliar with their potential health implications. We conducted a review to assess the impact of e-cigarettes and HNB products on urologic health.Material and methodsA bibliographic search covering the period up to April, 2021 was conducted using MEDLINE®/PubMed® and Google Scholar. Articles were reviewed and categorized based on the potential impact on erectile dysfunction, semen quality, lower urinary tract symptoms, genitourinary malignancies, and smoking cessation. Data were extracted, analyzed and summarized.ResultsMature data on the long-term impact of e-cigarette and HNB product use on urologic health are lacking. E-cigarette and HNB vapors appear to contain decreased concentrations of chemicals responsible for erectile dysfunction compared to tobacco smoke but may play a role through endothelial damage. Use of e-cigarettes is associated with lower sperm counts. No definitive data has shown a link between e-cigarette or HNB product use and lower urinary tract symptoms. Multiple carcinogens including those specifically linked to bladder cancer have been identified in the urine of e-cigarette and HNB product users. Limited data suggest e-cigarettes may aid in smoking cessation.ConclusionsUrologists may benefit from understanding the urologic health concerns surrounding e-cigarettes and HNB product use and patients may benefit from being properly educated.

The Interplay Between Respiratory Microbiota and Innate Immunity in Flavor E-Cigarette Vaping Induced Lung Dysfunction.

Global usage of electronic nicotine delivery systems (ENDS) has been increasing in the last decade. ENDS are non-combustible tobacco products that heat and aerosolize a liquid containing humectants, with added flavorings and often nicotine. Though ENDS are promoted as a less harmful alternative to smoking, current evidence links their use to a wide range of deleterious health effects including acute and chronic lung damage. ENDS can elicit an inflammatory response and impair the innate immune response in the lungs. Exposure to ENDS flavorings results in abnormal activation of the lung epithelial cells and β-defensins, dysfunction of the macrophage phagocytic activity, increased levels of mucin (MUC5AC) and abnormal activation of the neutrophilic response (NETosis). ENDS menthol flavorings disrupt innate immunity and might be associated with allergies and asthma through activation of transient receptor potential ankyrin 1 (TRAP1). Recent studies have expanded our understanding of the relationship between the homeostasis of lung innate immunity and the immunomodulatory effect of the host-microbiota interaction. Alterations of the normal respiratory microbiota have been associated with chronic obstructive pulmonary disease (COPD), asthma, atopy and cystic fibrosis complications which are strongly associated with smoking and potentially with ENDS use. Little is known about the short-and long-term effects of ENDS on the respiratory microbiota, their impact on the innate immune response and their link to pulmonary health and disease. Here we review the interaction between the innate immune system and the respiratory microbiota in the pathogenesis of ENDS-induced pulmonary dysfunction and identify future areas of research.

Switching to Progressively Reduced Nicotine Content Cigarettes in Smokers With Low Socioeconomic Status: A Double-Blind Randomized Clinical Trial.

The Food and Drug Administration issued an advanced notice of proposed rulemaking for setting a product standard for nicotine levels in cigarettes, with an emphasis on minimally or non-addicting very low nicotine content (VLNC). A 33 week, two-arm, double-blind randomized trial conducted in Hershey, Pennsylvania, USA and Washington, DC, USA included adult daily cigarette smokers (≥5 cigarettes per day) with less than a college degree, and who had no plans to quit within the next six months. Participants were randomized to either reduced nicotine content (RNC) study cigarettes tapered every three weeks to a final VLNC (0.2 mg/cigarette) for six weeks or to usual nicotine content (UNC) study cigarettes (11.6 mg/cigarette). Outcomes included acceptability of study cigarettes measured by attrition (primary outcome), compliance, reduction in cigarette dependence and tobacco biomarkers, and post-intervention cessation. The RNC (n = 122) versus UNC (n = 123) group had higher attrition (adjusted Hazard Ratio 3.4; 95% confidence interval [CI] 1.99 to 5.81). At the end of the intervention, cotinine levels were 50% lower in the RNC group (mean group difference -137 ng/mL; 95% CI -172, -102). The RNC group smoked fewer CPD (-4.1; 95% CI -6.44, -1.75) and had lower carbon monoxide levels (-4.0 ppm; 95% CI -7.7, -0.4). Forty seven percent (29/62) of the RNC group were biochemically-confirmed compliant with smoking VLNC cigarettes (mean cotinine = 8.9 ng/ml). At three month follow-up, only compliant VLNC smokers quit with an assisted quit attempt (N = 6/22, 27%). This study supports a VLNC standard in cigarettes. Differential dropout and noncompliance indicate some smokers had difficulty transitioning to cigarettes with reduced nicotine. These smokers will benefit from supplemental nicotine in medicinal or noncombustible tobacco products if a nicotine reduction standard is established. Other smokers successfully transitioned to very low nicotine content cigarettes exclusively and substantially reduced their exposure to nicotine.

Tobacco Product Use Among Adults - United States, 2019.

Cigarette smoking remains the leading cause of preventable disease and death in the United States (1). The prevalence of current cigarette smoking among U.S. adults has declined over the past several decades, with a prevalence of 13.7% in 2018 (2). However, a variety of combustible, noncombustible, and electronic tobacco products are available in the United States (1,3). To assess recent national estimates of tobacco product use among U.S. adults aged ≥18 years, CDC analyzed data from the 2019 National Health Interview Survey (NHIS). In 2019, an estimated 50.6 million U.S. adults (20.8%) reported currently using any tobacco product, including cigarettes (14.0%), e-cigarettes (4.5%), cigars (3.6%), smokeless tobacco (2.4%), and pipes* (1.0%).† Most current tobacco product users (80.5%) reported using combustible products (cigarettes, cigars, or pipes), and 18.6% reported using two or more tobacco products.§ The prevalence of any current tobacco product use was higher among males; adults aged ≤65 years; non-Hispanic American Indian/Alaska Native (AI/AN) adults; those whose highest level of educational attainment was a General Educational Development (GED) certificate; those with an annual household income <$35,000; lesbian, gay, or bisexual (LGB) adults; uninsured adults and those with Medicaid; those with a disability; or those with mild, moderate, or severe generalized anxiety disorder. E-cigarette use was highest among adults aged 18-24 years (9.3%), with over half (56.0%) of these young adults reporting that they had never smoked cigarettes. Implementing comprehensive, evidence-based, population level interventions (e.g., tobacco price increases, comprehensive smoke-free policies, high-impact antitobacco media campaigns, and barrier-free cessation coverage), in coordination with regulation of the manufacturing, marketing, and sale of all tobacco products, can reduce tobacco-related disease and death in the United States (1,4). As part of a comprehensive approach, targeted interventions are also warranted to reach subpopulations with the highest prevalence of use, which might vary by tobacco product type.

Metabolomic Analysis Identified Reduced Levels of Xenobiotics, Oxidative Stress, and Improved Vitamin Metabolism in Smokers Switched to Vuse Electronic Nicotine Delivery System.

IntroductionSwitching to noncombustible tobacco products presents an opportunity for cigarette smokers to potentially reduce the health risks associated with smoking. Electronic Nicotine Delivery Systems (ENDS) are one such product because the vapor produced from ENDS contains far fewer toxicants than cigarette smoke. To investigate the biochemical effects of switching from smoking to an ENDS, we assessed global metabolomic profiles of smokers in a 7-day confinement clinical study.MethodsIn the first 2 days of this clinical study, the subjects used their usual brand of cigarettes and then switched to exclusive ENDS ad libitum use for 5 days. Urine and plasma samples were collected at baseline and 5 days after switching. The samples were analyzed using a mass spectrometry-based metabolomic platform.ResultsRandom forest analyses of urine and plasma metabolomic data revealed excellent predictive accuracy (>97%) of a 30-metabolite signature that can differentiate smokers from 5-day ENDS switchers. In these signatures, most biomarkers are nicotine-derived metabolites or xenobiotics. They were significantly reduced in urine and plasma, suggesting a decreased xenobiotic load on subjects. Our results also show significantly decreased levels of plasma glutathione metabolites after switching, which suggests reduced levels of oxidative stress. In addition, increased urinary and plasma levels of vitamins and antioxidants were identified, suggesting enhanced bioavailability due to discontinuation of cigarette smoking and switching to Vuse ENDS use.ConclusionsOur results suggest reduced toxicant exposure, reduced oxidative stress, and potential beneficial changes in vitamin metabolism within 5 days in smokers switching to Vuse ENDS.ImplicationsSwitching from smoking to exclusive ENDS use in clinical confinement settings results in significant reduction of nicotine metabolites and other cigarette-related xenobiotics in urine and plasma of subjects. Significantly decreased oxidative stress-related metabolites and increased urinary and plasma levels of vitamin metabolites and antioxidants in 5-day short-term ENDS switchers suggest less toxic physiological environment for consumers of ENDS products and potential health benefits if such changes persist.

Cancer potencies and margin of exposure used for comparative risk assessment of heated tobacco products and electronic cigarettes aerosols with cigarette smoke

Health risk associated with the use of combustible cigarettes is well characterized and numerous epidemiological studies have been published for many years. Since more than a decade, innovative non-combusted tobacco products have emerged like heated tobacco products (HTP) or electronic cigarettes (EC). Long-term effects of these new products on health remain, however, unknown and there is a need to characterize associated potential health risks. The time dedicated to epidemiological data generation (at least 20 to 40 years for cancer endpoint), though, is not compatible with innovative development. Surrogates need, therefore, to be developed. In this work, non-cancer and cancer risks were estimated in a range of HTP and commercial combustible cigarettes based upon their harmful and potentially harmful constituent yields in aerosols and smoke, respectively. It appears that mean lifetime cancer risk values were decreased by more than one order of magnitude when comparing HTPs and commercial cigarettes, and significantly higher margin of exposure for non-cancer risk was observed for HTPs when compared to commercial cigarettes. The same approach was applied to two commercial ECs. Similar results were also found for this category of products. Despite uncertainties related to the factors used for the calculations and methodological limitations, this approach is valuable to estimate health risks associated to the use of innovative products. Moreover, it acts as predictive tool in absence of long-term epidemiological data. Furthermore, both cancer and non-cancer risks estimated for HTPs and ECs highlight the potential of reduced risk for non-combusted products when compared to cigarette smoking.

Analysis of the safety of using e-cigarettes during pregnancy. The literature review

Introduction and objective: The popularity of e-cigarettes around the world has been increasing in recent years. The reason for this may be a relatively lower cost of use and a lower amount of toxins compared to traditional cigarettes. E-cigarettes are more often picked by women of reproductive age compared to the general group of women. Abbreviated description of the state of knowledge: According to recent studies, pregnant women consider e-cigarettes safer than tobacco cigarettes, which may be due to being advertised as a less harmful product compared to traditional cigarettes. Although some electronic cigarettes do not contain nicotine, they also consist of glycol, glycerin, fragrances and heavy metals that may adversely affect the development of the fetus. Furthermore, the statements of some significant healthcare institutions are divided on the safe use of e-cigarettes by pregnant women, even in the case of treating them as an aid in the smoking cessation process. Summary: No clear understanding is noticed regarding the effects of using electronic nicotine delivery systems during pregnancy on maternal, fetal or newborn health, so there is a high need of further studies assessing the safety of these noncombustible tobacco products. However, it can be an feasible alternative to traditional cigarettes, when trying to quit smoking by pregnant women.

Comparison of End Tidal Carbon Monoxide Levels between Conventional Cigarette, Electronic Cigarette and Heated Tobacco Product among Asiatic Smokers

Background Electronic nicotine delivery systems (ENDS) and heated tobacco products (HTPs) are noncombustible tobacco products which have been found to generate aerosols containing lower levels of Harmful and Potentially Harmful Constituents (HPHCs) in comparison to conventional cigarettes. Objective: This quasi experimental study measured and compared the end tidal carbon monoxide (eCO) levels of participants after use of ENDS, HTPs and conventional cigarettes. Methods: In total 45 smokers, each smoking at least 10 conventional cigarettes per day for 5 years participated in the study. Based on their preference, participants used only one of the tobacco products (ENDS, HTPs, or conventional cigarette) and were briefed about the product use based on manufacturer’s instructions. The eCO levels were obtained at baseline, followed by 5, 10, 15, 30 and 45 min respectively after the product use. Results: There was significant increase in eCO levels for conventional cigarettes as compared to other modes. Peak eCO levels of 20.2 ± 0.86 ppm, 8.8 ± 1.56 ppm and 6.0 ± 1.36 ppm was achieved at 30 min, 15 min and 10 min for conventional cigarettes, ENDS and HTPs respectively. However, the levels were significantly lower in ENDS and HTPs. Conclusion: Even though ENDS and HTPs may have produced significantly lower eCO than conventional cigarettes, the significantly increasing levels over time from baseline which was not shown before is a cause of concern. As of now, their use as an alternate to cigarettes needs to be considered under regulatory framework.

Association of initial e-cigarette and other tobacco product use with subsequent cigarette smoking in adolescents: a cross-sectional, matched control study

IntroductionThis study assessed whether initiating e-cigarette use increases the uptake of cigarette smoking in US adolescents compared with behavioural and synthetic controls.MethodsData come from 78 265 adolescents in the National...

PhenX: Host: Social/Cognitive measures for tobacco regulatory research

A working group (WG) of experts from diverse fields related to nicotine and tobacco addiction was convened to identify elements and measures from the Host: Social/Cognitive domain to include in...

PhenX: Host: Biobehavioral measures for tobacco regulatory research

A working group (WG) of experts from diverse fields related to nicotine and tobacco addiction was constituted to identify constructs and measures for the PhenX (Phenotypes and eXposures) Tobacco Regulatory...

Urinary Leukotriene E4 and 2,3-Dinor Thromboxane B2 Are Biomarkers of Potential Harm in Short-Term Tobacco Switching Studies.

Modified risk tobacco products (MRTP) can reduce harm by decreasing exposure to combustion-related toxicants. In the absence of epidemiologic data, biomarkers of potential harm (BoPH) are useful to evaluate the harm-reducing potential of MRTPs. This study evaluated whether arachidonic acid (AA)-derived metabolites serve as short-term BoPH for predicting harm reduction in tobacco product-switching studies. We used 24-hour urine samples from participants in a series of short-term studies in which smokers switched from combustible to noncombustible tobacco products [oral smokeless tobacco products or electronic nicotine delivery system (ENDS)] or abstinence. Pre- and postswitching samples were analyzed by LC/MS-MS for alterations in select AA metabolites, including prostaglandins, isoprostanes, thromboxanes, and leukotrienes. Switching to abstinence, dual use of combustible and noncombustible products, or exclusive use of noncombustible products resulted in reduced 2,3-d-TXB2 levels. Moreover, switching smokers to either abstinence or exclusive use of oral tobacco products resulted in reduced LTE4, but dual use of combustible and oral tobacco products or ENDS did not. A two-biomarker classification model comprising 2,3-d-TXB2 and LTE4 demonstrated the highest performance in distinguishing smokers switched to either abstinence or to ENDS and oral smokeless tobacco products. Urinary 2,3-d-TXB2 and LTE4 can discriminate between combustible tobacco users and combustible tobacco users switched to either abstinence or noncombustible products for 5 days. 2,3-d-TXB2 and LTE4, which are linked to platelet activation and inflammation, represent BoPH in short-term tobacco product-switching studies. Thus, from a regulatory perspective, 2,3-d-TXB2 and LTE4 may aid in assessing the harm reduction potential of MRTPs.

Oral Health Effects of Combusted and Smokeless Tobacco Products.

The oral cavity is usually the first part of a consumer's body exposed to the constituents of tobacco products or their emissions. Consequently, the oral cavity is a frequent site for carcinogenic, microbial, immunologic, and clinical effects of tobacco use. This article summarizes 5 presentations on various aspects of oral health affected by combusted or noncombusted tobacco products from a recent conference, "Oral Health Effects of Tobacco Products: Science and Regulatory Policy," sponsored by the American Association for Dental Research and the Food and Drug Administration.

Looking Back and Ahead: The Food and Drug Administration's Regulation of the Tobacco Industry and Next-Generation Products.

Regulatory policy toward tobacco significantly affects oral health because tobacco use is a driver of diseases that manifest themselves in or near the oral cavity. Tobacco use in the United States has been associated with millions of cases of periodontal disease. Researchers have identified the role of combusted and noncombusted tobacco products in promoting cancers of the head and neck, leading to disease and premature death. Tobacco companies have moved increasingly toward so-called next-generation products (NGPs)-products that may emit fewer toxins than combustible forms of tobacco. Although NGPs may negatively affect the lungs and other bodily systems, they shift the injection site of nicotine from the lungs to the oral cavity and oral tissues. Because the long-term effects of NGPs are unknown, this tobacco marketing development has profound implications for oral disease. The US Food and Drug Administration exercises regulatory authority over tobacco products. The tobacco industry has avoided meaningful regulation of its products, especially smokeless forms. By publishing new research, oral health scientists can meaningfully shape the climate in which the administration's policy making occurs.

Defining and Measuring Abstinence in Clinical Trials of Smoking Cessation Interventions: An Updated Review.

Changes in tobacco products, use patterns, and assessment technology in the last 15 years led the Society for Research on Nicotine and Tobacco (SRNT) Treatment Research Network to call for an update to the 2003 SRNT recommendations for assessing abstinence in clinical trials of smoking cessation interventions. The SRNT Treatment Research Network convened a group of investigators with decades of experience in conducting tobacco treatment clinical trials. To arrive at the updated recommendations, the authors reviewed the recommendations of the prior SRNT Workgroup as well as current literature. Ten additional experts in the field provided feedback on this paper and these recommendations. With respect to defining abstinence, the authors recommend: (1) continuing to use the definition of no use of combustible tobacco products (regardless of use of noncombustible tobacco products [e.g., snus] and alternative products [e.g., e-cigarettes]) and collecting additional data to permit alternate abstinence definitions; (2) no use of combustible or smokeless tobacco products; and (3) no use of combustible or smokeless tobacco products or alternative products, as appropriate for the research question being addressed. The authors also recommend reporting point prevalence and prolonged abstinence at multiple timepoints (end of treatment, ≥3 months after the end of treatment, and ≥6 months postquit or posttreatment initiation). Defining abstinence requires specification of which products a user must abstain from using, the type of abstinence (i.e., point prevalence or continuous), and the duration of abstinence. These recommendations are intended to serve as guidelines for investigators as they collect the necessary data to accurately describe participants' abstinence during smoking cessation clinical trials. This paper provides updated recommendations for defining abstinence in the context of smoking cessation treatment clinical trials.

Patterns of tobacco use among smokers prior to hospitalization for an acute cardiac event: Use of combusted and non-combusted products

Use of tobacco products before or after a cardiac event increases risk of morbidity and mortality. Unlike cigarette smoking, which is generally screened in the healthcare system, identifying the use of other tobacco products remains virtually unexplored. This study aimed at characterizing the use of other non-combusted tobacco products in addition to combusted products among cardiac patients and identifying a profile of patients who are more likely to use non-combusted products. Patients (N = 168) hospitalized for a coronary event who reported being current cigarette smokers completed a survey querying sociodemographics, cardiac diagnoses, use of other tobacco products, and perceptions towards these products. Classification and regression tree (CART) analysis was used to identify which interrelationships of participants characteristics led to profiles of smoking cardiac patients more likely to also be using non-combusted tobacco products. Results showed that non-combusted tobacco product use ranged from 0% to 47% depending on patient characteristic combinations. Younger age and lower perception that cigarette smoking is responsible for their cardiac condition were the strongest predictive factors for use of non-combusted products. Tobacco product use among cardiac patients extends beyond combusted products (13.7% non-combusted product use), and consequently, screening in health care settings should be expanded to encompass other tobacco product use. This study also characterizes patients likely to be using non-combusted products in addition to combusted, a group at high-risk due to their multiple product use, but also a group that may be amenable to harm reduction approaches and evidence-based tobacco treatment strategies.